CN111108433B

CN111108433B - Method for manufacturing liquid crystal element

Info

Publication number: CN111108433B
Application number: CN201880060453.XA
Authority: CN
Inventors: 奥田隆一; 植阪裕介; 小山贵由
Original assignee: JSR Corp
Current assignee: JSR Corp
Priority date: 2017-11-20
Filing date: 2018-10-09
Publication date: 2022-07-12
Anticipated expiration: 2038-10-09
Also published as: TW201928478A; JPWO2019097902A1; WO2019097902A1; KR102321076B1; TWI776974B; JP7074142B2; KR20200042002A; CN111108433A

Abstract

The invention provides a liquid crystal element with excellent reliability in an element structure in which an interlayer insulating film, a pattern electrode and a liquid crystal alignment film are sequentially formed on a substrate. A method of manufacturing a liquid crystal element, comprising: a step of forming an interlayer insulating film (21) on at least one of the pair of substrates; a step of forming a pattern electrode (pixel electrode (19)) on the interlayer insulating film (21); and a step of forming a liquid crystal alignment film (first alignment film (32)) on the pattern electrode so as to be in contact with at least a part of the interlayer insulating film (21), wherein the liquid crystal alignment film is formed using a liquid crystal aligning agent containing a polymer component and at least one solvent selected from a specific solvent group.

Description

Method for manufacturing liquid crystal element

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is based on japanese patent application No. 2017-223114 filed on 2017, 11/20, and the contents of the description thereof are incorporated herein.

Technical Field

The present disclosure relates to a method of manufacturing a liquid crystal element.

Background

As liquid crystal devices, various devices such as a horizontal Alignment mode using a Nematic liquid crystal having positive dielectric anisotropy, a Vertical Alignment (VA) mode using a Vertical (homeotropic) Alignment mode using a Nematic liquid crystal having negative dielectric anisotropy, and the like are known, as typified by a Twisted Nematic (TN) mode, a Super Twisted Nematic (STN) mode, and the like. In addition, a liquid crystal device having a lateral electric Field mode such as an In-Plane Switching (IPS) mode, a Fringe Field Switching (FFS) mode, or the like, which has a cell structure In which a pair of electrodes is provided on one substrate, is also known.

As one of Alignment processing methods of liquid crystal devices, a Polymer Stabilized Alignment (PSA) method is known (for example, see patent document 1). The PSA method is as follows: in the gap between the pair of substrates, a photopolymerizable monomer is mixed with a liquid crystal in advance to construct a liquid crystal cell, and then, ultraviolet rays are irradiated while a voltage is applied between the substrates to polymerize the photopolymerizable monomer, thereby forming a polymer layer, and the initial orientation of the liquid crystal is controlled by the polymer layer. By the above-described technique, the field angle can be enlarged and the response speed of liquid crystal molecules can be increased, and thus the problem of insufficient transmittance and contrast in a Multi-domain Vertical Alignment (MVA) type panel can be solved.

Patent document 1 discloses the following cases: in the PSA technology, a pattern electrode patterned so as to have a comb-shaped package (also referred to as a fishbone shape) having a large number of openings (slit portions) is used as a pixel electrode. In the liquid crystal device of patent document 1, a drain bus line (drain busline) is formed on a glass substrate on the array substrate side, and an interlayer insulating film is formed thereon. Further, a fishbone-shaped pixel electrode is formed on the interlayer insulating film, and a liquid crystal alignment film is formed on the pixel electrode. The liquid crystal alignment film is generally formed by dissolving a polymer component such as polyamic acid, polyimide, polyorganosiloxane, (meth) acrylic polymer, or polyamide in a solvent, applying the polymer composition to a substrate, and removing the solvent.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open No. 2003-149647

Disclosure of Invention

Problems to be solved by the invention

In the case where a pattern electrode having a large number of slit portions is disposed on an interlayer insulating film and a liquid crystal alignment film is formed thereon, a liquid crystal alignment agent and the interlayer insulating film come into contact in the slit portions in a pixel region (i.e., a display region) of a liquid crystal device. In such a case, there are the following concerns: the interlayer insulating film is affected by the liquid crystal aligning agent to change its characteristics, or impurity components contained in the interlayer insulating film are eluted into the liquid crystal aligning agent to degrade the performance of the liquid crystal alignment film, which lowers the reliability of the liquid crystal device.

The present disclosure has been made in view of the above problems, and an object thereof is to provide a method for manufacturing a liquid crystal element, which can obtain a liquid crystal element having excellent reliability in an element structure in which an interlayer insulating film, a pattern electrode, and a liquid crystal alignment film are sequentially formed on a substrate.

Means for solving the problems

The present disclosure adopts the following means to solve the above problems.

< 1 > a method for manufacturing a liquid crystal element including a pair of substrates disposed to face each other, a liquid crystal layer disposed between the pair of substrates, and a pair of electrodes, wherein at least one of the pair of electrodes is a pattern electrode having a plurality of openings, the method comprising: a step of forming an interlayer insulating film on at least one of the pair of substrates; a step of forming the pattern electrode on the interlayer insulating film; and a step of forming a liquid crystal alignment film on the pattern electrode so as to be in contact with at least a part of the interlayer insulating film, the liquid crystal alignment film being formed using a liquid crystal aligning agent containing a polymer component and at least one solvent selected from a group of solvents shown below.

Solvent group:

[A] solvent: a compound represented by the following formula (1), a compound represented by the following formula (2), N, 2-trimethylpropanamide, and 1, 3-dimethyl-2-imidazolidinone.

[B] Solvent: dipropylene glycol monomethyl ether, dipropylene glycol dimethyl ether, diethylene glycol monoethyl ether, 4-methoxy-4-methyl-2-pentanone, 4-hydroxy-2-butanone, 2-methyl-2-hexanol, 2, 6-dimethyl-4-heptanol, diisobutyl ketone, propylene glycol diacetate, diethylene glycol diethyl ether, diisoamyl ether, diacetone alcohol, and propylene glycol monobutyl ether.

[ solution 1]

(in the formula (1), R¹A monovalent hydrocarbon group having 2 to 5 carbon atoms or a monovalent group having "-O-" between carbon-carbon bonds in the hydrocarbon group)

[ solution 2]

(in the formula (2), R²And R³Each independently represents a hydrogen atom, a monovalent hydrocarbon group having 1 to 6 carbon atoms, or a monovalent group having "-O-" between carbon-carbon bonds of the hydrocarbon group, R²And R³Can bond with each other to form a ring structure; r⁴Alkyl group having 1 to 6 carbon atoms)

ADVANTAGEOUS EFFECTS OF INVENTION

According to the above configuration, even when the interlayer insulating film is in contact with the liquid crystal alignment agent in the opening of the pattern electrode when the liquid crystal alignment film is formed, the performance of the interlayer insulating film or the liquid crystal alignment film is not easily degraded, and a liquid crystal element having excellent reliability can be obtained.

Drawings

Fig. 1 is a diagram schematically showing a part of a liquid crystal device.

Fig. 2 is a cross-sectional view schematically showing a part of a liquid crystal device according to a first embodiment.

Fig. 3 is a cross-sectional view schematically showing a part of a liquid crystal device according to a second embodiment.

Fig. 4 is a diagram showing the structure of an electrode used in the example.

Fig. 5 is a diagram showing the structure of an electrode used in the example.

Description of the symbols

1: ITO electrode

2: slit part

3: light shielding film

10: liquid crystal device having a plurality of liquid crystal cells

14: thin film transistor

15: array substrate

16: opposite substrate

17: liquid crystal layer

19: pixel electrode

19 c: slit part

21: interlayer insulating film

29: color filter layer

29 a: colored pattern

29 b: interlayer insulating film

31: common electrode

32: first alignment film

33: second alignment film

34. 35: PSA layer (orientation control layer)

Detailed Description

Hereinafter, embodiments will be described with reference to the drawings. In the following embodiments, the same or equivalent portions are denoted by the same reference numerals in the drawings, and the same portions are referred to by the same reference numerals.

(constitution of liquid Crystal device 10)

The liquid crystal device 10 is a vertical Alignment type liquid crystal display element of a Polymer Stabilized Alignment (PSA) system. In the display portion of the liquid crystal device 10, a plurality of pixels 11 are arranged in a matrix. As shown in fig. 1, the pixels 11 are formed in a region surrounded by the scanning signal lines 12 and the image signal lines 13 which intersect with each other. In each pixel 11, a Thin Film Transistor (TFT) 14 functioning as a liquid crystal driving element is disposed. As shown in fig. 2, the liquid crystal device 10 includes an array substrate 15, an opposite substrate 16, and a liquid crystal layer 17.

The array substrate 15 includes a transparent substrate 18 such as a glass substrate or a plastic substrate, scanning signal lines 12, video signal lines 13, thin film transistors 14, pixel electrodes 19, and an interlayer insulating film 21 (see fig. 2). The thin film transistor 14 includes: a gate electrode 22 including the scanning signal line 12, a semiconductor layer 23 including silicon (Si), a source electrode 24 including the video signal line 13, and a drain electrode 25 connected to the pixel electrode 19. The thin film transistor 14 is provided by a known method such as photolithography. As a specific material constituting each part of the thin film transistor 14, a known material can be used.

The pixel electrode 19 is formed of a transparent conductor such as Indium Tin Oxide (ITO). As shown in fig. 1, the pixel electrode 19 is a pattern electrode in which a plurality of slit portions (elongated rectangular openings) 19c are provided in a planar electrode. Specifically, the pixel electrode 19 includes: the conductive portion and the non-conductive portion have a repetitive pattern of a main line portion 19a extending in two mutually orthogonal directions, a plurality of branch line portions 19b extending in an oblique direction from the main line portion 19a, and a plurality of slit portions 19c formed between the plurality of branch line portions 19 b. The pixel electrode 19 is electrically connected to the thin film transistor 14. The thin film transistor 14 is electrically connected to the scanning signal line 12 and the video signal line 13, and is supplied with various signals.

The array substrate 15 has the following structure: in a display region in which a plurality of pixels 11 are arranged in a matrix, a transparent substrate 18, an interlayer insulating film 21, and a pixel electrode 19 are sequentially stacked. The pixel electrode 19 is connected to the drain electrode 25 via a contact hole 27 provided in the interlayer insulating film 21. The interlayer insulating film 21 is formed by photolithography using a radiation-sensitive resin composition described later. By providing the interlayer insulating film 21, an increase in capacitive coupling between the pixel electrode 19 and the signal line is suppressed.

The counter substrate 16 includes a glass substrate 28, a color filter layer 29, an overcoat layer (not shown) as an insulating layer, and a common electrode 31. The color filter layer 29 includes sub-pixels colored in red (R), green (G), and blue (B). The color filter layer 29 is manufactured by a known method such as photolithography. The common electrode 31 is a planar electrode made of a transparent conductor such as ITO, and is provided across the plurality of pixels 11.

A first alignment film 32 is formed on the electrode formation surface of the array substrate 15, and a second alignment film 33 is formed on the electrode formation surface of the counter substrate 16. The first alignment film 32 and the second alignment film 33 are liquid crystal alignment films that define alignment of liquid crystal molecules in the liquid crystal layer 17, and are formed on the substrate using a liquid crystal alignment agent that is a polymer composition containing a polymer component. The first alignment film 32 is in contact with the interlayer insulating film 21 in the display region at least in the slit portion 19 c.

The array substrate 15 and the counter substrate 16 are arranged with a predetermined gap (cell gap) provided so that the alignment film formation surface of the array substrate 15 faces the alignment film formation surface of the counter substrate 16. The peripheral edges of the pair of substrates disposed to face each other are bonded together with a sealant (not shown). As a material of the sealant, a material (for example, thermosetting resin or photocurable resin) known as a sealant for a liquid crystal device can be used. The liquid crystal composition is filled in a space surrounded by the array substrate 15, the counter substrate 16, and the sealant, and thereby the liquid crystal layer 17 is disposed so as to be in contact with the first alignment film 32 and the second alignment film 33.

The liquid crystal layer 17 has negative dielectric anisotropy. The liquid crystal layer 17 includes a PSA layer 34 and a PSA layer 35 as polymer layers at an interface with the array substrate 15 and an interface with the counter substrate 16, respectively. The PSA layer 34 and the PSA layer 35 are formed by photopolymerizing a photopolymerizable monomer that has been mixed into the liquid crystal layer 17 in advance, with the liquid crystal molecules being aligned in a pre-tilt state after the liquid crystal cell is constructed. In the liquid crystal device 10, the initial alignment of the liquid crystal molecules in the liquid crystal layer 17 is controlled by the PSA layers 34 and 35.

In the liquid crystal device 10, a polarizing plate 36 and a polarizing plate 37 are disposed outside the array substrate 15 and the counter substrate 16, respectively. A terminal area is provided in an outer edge portion of the array substrate 15, and a driver Integrated Circuit (IC) or the like for driving the liquid crystal is connected to the terminal area to drive the liquid crystal device 10.

< liquid Crystal Aligning agent >

Next, a liquid crystal aligning agent for forming the liquid crystal alignment films (the first alignment film 32 and the second alignment film 33) will be described. The liquid crystal aligning agent contains a polymer component and a solvent component.

(Polymer component)

The main skeleton of the polymer contained in the liquid crystal aligning agent is not particularly limited, and examples thereof include: a main skeleton such as polyamic acid, polyamic acid ester, polyimide, polyorganosiloxane, polyester, cellulose derivative, polyacetal, polystyrene derivative, poly (styrene-phenylmaleimide) derivative, or poly (meth) acrylic polymer. Among these, at least one polymer (hereinafter, also referred to as "P polymer") selected from the group consisting of polyamic acid, polyamic acid ester, polyimide, and polyorganosiloxane is preferable. In the preparation of the liquid crystal aligning agent, one kind of the polymer may be used alone, or two or more kinds may be used in combination. In the present specification, "(meth) acrylic acid" is defined to include "acrylic acid" and "methacrylic acid".

The method for synthesizing the [ P ] polymer is not particularly limited. For example, in the case where the [ P ] polymer is a polyamic acid, the polyamic acid can be obtained by reacting a tetracarboxylic dianhydride with a diamine.

(Polyamic acid)

Examples of tetracarboxylic acid dianhydride used for synthesis of polyamic acid include: aliphatic tetracarboxylic acid dianhydride, alicyclic tetracarboxylic acid dianhydride, aromatic tetracarboxylic acid dianhydride, and the like. Specific examples of these include aliphatic tetracarboxylic dianhydrides such as: 1,2,3, 4-butanetetracarboxylic dianhydride, ethylenediaminetetraacetic dianhydride, etc.;

examples of the alicyclic tetracarboxylic dianhydride include: 1,2,3, 4-cyclobutanetetracarboxylic dianhydride, 1, 3-dimethyl-1, 2,3, 4-cyclobutanetetracarboxylic dianhydride, 2,3, 5-tricarboxycyclopentylacetic dianhydride, 1,3,3a,4,5,9 b-hexahydro-5- (tetrahydro-2, 5-dioxo-3-furanyl) -naphtho [1,2-c ] furan-1, 3-dione, 1,3,3a,4,5,9 b-hexahydro-8-methyl-5- (tetrahydro-2, 5-dioxo-3-furanyl) -naphtho [1,2-c ] furan-1, 3-dione, 3-oxabicyclo [3.2.1] octane-2, 4-dione-6-spiro-3 '- (tetrahydrofuran-2', 5' -dione), 5- (2, 5-dioxotetrahydro-3-furanyl) -3-methyl-3-cyclohexene-1, 2-dicarboxylic anhydride, 2,4,6, 8-tetracarboxybicyclo [3.3.0] octane-2: 4,6: 8-dianhydride, cyclohexanetetracarboxylic dianhydride, cyclopentanetetracarboxylic dianhydride, etc.;

Examples of the aromatic tetracarboxylic dianhydride include: tetracarboxylic dianhydride described in Japanese patent application laid-open No. 2010-97188 can be used in addition to pyromellitic dianhydride, 4' - (hexafluoroisopropylidene) diphthalic anhydride, p-phenylene bis (trimellitic acid monoester anhydride), ethylene glycol bis (trimellitic acid anhydride), and 1, 3-propanediol bis (trimellitic acid anhydride). Further, the tetracarboxylic dianhydride may be used alone or in combination of two or more.

The tetracarboxylic dianhydride used for the synthesis preferably contains an alicyclic tetracarboxylic dianhydride, and more preferably contains a tetracarboxylic dianhydride having the following ring structure (hereinafter also referred to as "specific tetracarboxylic dianhydride") in terms of enabling the obtained polymer to have higher solubility in a solvent: the ring structure is at least one selected from the group consisting of a cyclobutane ring, a cyclopentane ring and a cyclohexane ring. The proportion of the specific tetracarboxylic dianhydride used is preferably 10 mol% or more, and more preferably 20 mol% to 100 mol% based on the total amount of the tetracarboxylic dianhydride used for synthesis of the polyamic acid.

Examples of the diamine used for the synthesis of the polyamic acid include: aliphatic diamines, alicyclic diamines, aromatic diamines, diaminoorganosiloxanes, and the like. Specific examples of these include the aliphatic diamines: m-xylylenediamine, 1, 3-propylenediamine, tetramethylenediamine, hexamethylenediamine, 1, 3-bis (aminomethyl) cyclohexane, etc.; examples of the alicyclic diamine include: 1, 4-diaminocyclohexane, 4' -methylenebis (cyclohexylamine), and the like;

Examples of the aromatic diamine include: p-phenylenediamine, 4' -diaminodiphenylmethane, 4' -diaminodiphenylsulfide, 1, 5-diaminonaphthalene, 2' -dimethyl-4, 4' -diaminobiphenyl, 4' -diamino-2, 2' -bis (trifluoromethyl) biphenyl, 4' -diaminodiphenylether, 1, 3-bis (4-aminophenoxy) ethane, 1, 3-bis (4-aminophenoxy) propane, 9-bis (4-aminophenyl) fluorene, 2-bis [4- (4-aminophenoxy) phenyl ] hexafluoropropane, 4' - (p-phenylenediisopropylidene) dianiline, 1, 4-bis (4-aminophenoxy) benzene, 2, 6-diaminopyridine, 1, 4' -diaminonaphthalene, 2, 4' -diaminodiphenylether, 4' -diaminonaphthalene, 2, 4' -diaminonaphthalene, 4' -diamino-bis (4-aminophenoxy) benzene, 2, 6-diaminopyridine, and the like, 3, 6-diaminocarbazole, N' -bis (4-aminophenyl) benzidine, 1, 4-bis- (4-aminophenyl) -piperazine, 1- (4-aminophenyl) -2, 3-dihydro-1, 3, 3-trimethyl-1H-inden-5-amine, 1- (4-aminophenyl) -2, 3-dihydro-1, 3, 3-trimethyl-1H-inden-6-amine, 3, 5-diaminobenzoic acid, cholestanoxy-3, 5-diaminobenzene (cholestanoxy-3, 5-diaminobenzene), cholestanoxy-2, 4-diaminobenzene (cholestanyloxy-2, 4-diaminobenzole), cholestanyl3,5-diaminobenzoate (cholestanyl3,5-diaminobenzoate), cholestanyl3,5-diaminobenzoate (cholestanyl3,5-diaminobenzoate), lanostanyl 3,5-diaminobenzoate (lanostanyl 3,5-diaminobenzoate), 3,6-bis (4-aminobenzoyloxy) cholestane (3,6-bis (4-aminobenzoyloxy) cholestane), 4- (4' -trifluoromethoxybenzoyloxy) cyclohexyl-3, 5-diaminobenzoate, 1-bis (4- ((aminophenyl) methyl) phenyl) -4-heptylcyclohexane, 1-bis (4- ((aminophenyl) methyl) phenyl) -4- (4-heptylcyclohexyl) cyclohexane, 2, 4-diamino-N, N-diallylaniline, 4-aminobenzylamine, N- [4- (2-aminoethyl) phenyl ] benzene-1, 4-diamine, N- [4- (aminomethyl) phenyl ] benzene-1, 4-diamine, 1, 3-bis (4-aminophenyl) urea, 4'- [4,4' -propane-1, 3-diylbis (piperidine-1, 4-diyl) ] diphenylamine, 2-propynyloxy-2, 4-phenylenediamine and the following formula (D-1)

[ solution 3]

(in the formula (D-1), X^IAnd X^IIEach independently represents a single bond, -O-, -COO-, -OCO-or-NH-CO- (wherein the bond having the bond is bonded to the diaminophenyl group), R^IAnd R^IIEach independently is an alkanediyl group having 1 to 3 carbon atoms, a is 0 or 1, b is an integer of 0 to 2, c is an integer of 1 to 20, n is 0 or 1, and m is 0 or 1; wherein a and b are not both 0 at the same time, in X^IIn the case of-NH-CO-, n is 0)

The compounds represented by the formula (I), etc.;

examples of the diaminoorganosiloxanes include: 1, 3-bis (3-aminopropyl) -tetramethyldisiloxane, etc.; in addition, diamines described in Japanese patent application laid-open No. 2010-97188 can be used. In the synthesis of the polyamic acid, one kind of diamine may be used alone or two or more kinds may be used in combination.

The polyamic acid can be obtained by reacting the tetracarboxylic dianhydride and the diamine as described above, and optionally a molecular weight modifier. The ratio of the tetracarboxylic dianhydride to the diamine used in the synthesis reaction of the polyamic acid is preferably 0.2 to 2 equivalents of the acid anhydride group of the tetracarboxylic dianhydride to 1 equivalent of the amino group of the diamine. Examples of the molecular weight regulator include: acid monoanhydrides such as maleic anhydride, phthalic anhydride, and itaconic anhydride; monoamine compounds such as aniline, cyclohexylamine, and n-butylamine; and monoisocyanate compounds such as phenyl isocyanate and naphthyl isocyanate. The ratio of the molecular weight modifier used is preferably 20% by mass or less based on the total amount of the tetracarboxylic dianhydride and the diamine used.

The synthesis reaction of the polyamic acid is preferably carried out in an organic solvent. The reaction temperature in this case is preferably-20 ℃ to 150 ℃ and the reaction time is preferably 0.1 hour to 24 hours.

Examples of the organic solvent used in the reaction include: aprotic polar solvents, phenolic solvents, alcohols, ketones, esters, ethers, halogenated hydrocarbons, and the like. The organic solvent is preferably one or more selected from the group consisting of N-methyl-2-pyrrolidone, N-dimethylacetamide, N-dimethylformamide, dimethyl sulfoxide, γ -butyrolactone, tetramethylurea, hexamethylphosphoric triamide, m-cresol, xylenol, a halogenated phenol, and a specific solvent described later, or a mixture of one or more of these and another organic solvent (e.g., butyl cellosolve, diethylene glycol diethyl ether, etc.). The amount of the organic solvent used is preferably such that the total amount of the tetracarboxylic dianhydride and the diamine is 0.1 to 50 mass% relative to the total amount of the reaction solution. In this manner, a reaction solution obtained by dissolving the polyamide acid can be obtained. The reaction solution can be directly used for preparing the liquid crystal aligning agent, or used for preparing the liquid crystal aligning agent after the polyamic acid contained in the reaction solution is isolated.

(polyimide)

The polyimide can be obtained by subjecting a polyamic acid synthesized as described to dehydrate ring closure and imidization. The polyimide may be a complete imide product obtained by dehydration ring closure of all the amic acid structures of the polyamic acid as a precursor thereof, or may be a partial imide product obtained by dehydration ring closure of only a part of the amic acid structures and coexistence of the amic acid structure and the imide ring structure. The polyimide preferably has an imidization ratio of 30% or more, more preferably 40% to 99%, and still more preferably 60% to 99%. The imidization ratio is a percentage representing a ratio of the number of imide ring structures to a total of the number of amic acid structures and the number of imide ring structures of the polyimide. Here, a part of the imide ring may be an imide ring.

The dehydration ring closure of the polyamic acid is preferably performed by the following method: dissolving polyamide acid in organic solvent, adding dehydrating agent and dehydration ring-closing catalyst into the solution, and heating if necessary. In the above method, as the dehydrating agent, for example, an acid anhydride such as acetic anhydride, propionic anhydride, trifluoroacetic anhydride or the like can be used. The amount of the dehydrating agent to be used is preferably 0.01 to 20 mol based on 1 mol of the amic acid structure of the polyamic acid. As the dehydration ring-closure catalyst, for example, pyridine, collidine, lutidine, triethylamine and other tertiary amines can be used. The amount of the dehydration ring-closing catalyst to be used is preferably 0.01 to 10 mol based on 1 mol of the dehydrating agent to be used. Examples of the organic solvent used include organic solvents exemplified as users for synthesizing polyamic acid. The reaction temperature of the dehydration ring-closing reaction is preferably 0 ℃ to 180 ℃, and the reaction time is preferably 1.0 hour to 120 hours. The obtained reaction solution can be directly used for preparing the liquid crystal aligning agent, and also can be used for preparing the liquid crystal aligning agent after the polyamic acid is isolated.

(polyamic acid ester)

The polyamic acid ester can be obtained, for example, by the following method: [I] a method of reacting the polyamic acid obtained by the reaction with an esterifying agent; [ II ] a method for reacting a tetracarboxylic acid diester with a diamine; [ III ] A method for reacting a tetracarboxylic acid diester dihalide with a diamine, and the like. Examples of the esterifying agent of [ I ] include methanol and ethanol. The tetracarboxylic acid diester used in the above-mentioned [ II ] can be obtained by ring-opening a tetracarboxylic acid dianhydride with an alcohol or the like. The tetracarboxylic acid diester dihalide used in the above [ III ] can be obtained by reacting the tetracarboxylic acid diester obtained as described above with an appropriate chlorinating agent such as thionyl chloride. The polyamic acid ester obtained may have only the amic acid ester structure or may be a partially esterified product in which the amic acid structure and the amic acid ester structure coexist. The reaction solution obtained by dissolving the polyamic acid ester may be used as it is for the preparation of the liquid crystal aligning agent, or the polyamic acid ester contained in the reaction solution may be isolated and then used for the preparation of the liquid crystal aligning agent.

The polyamic acid, polyamic acid ester, and polyimide obtained in the above manner are preferably those having a solution viscosity of 10 to 800 mPas, more preferably 15 to 500 mPas, when prepared in a solution having a concentration of 10% by mass. The solution viscosity (mPa · s) of the polymer is a value measured at 25 ℃ with an E-type rotational viscometer for a 10 mass% polymer solution prepared using a good solvent for the polymer (e.g., γ -butyrolactone, N-methyl-2-pyrrolidone, etc.). The polyamic acid, polyamic acid ester, and polyimide preferably have a weight average molecular weight of 500 to 100,000, more preferably 1,000 to 50,000, in terms of polystyrene, as measured by Gel Permeation Chromatography (GPC).

(polyorganosiloxane)

The polyorganosiloxane can be obtained by, for example, hydrolyzing or hydrolyzing and condensing a hydrolyzable silane compound preferably in the presence of an appropriate organic solvent, water and a catalyst.

Examples of the hydrolyzable silane compound used for the synthesis of polyorganosiloxane include: alkoxysilane compounds such as tetramethoxysilane, tetraethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, trimethoxysilylpropylsuccinic anhydride, dimethyldimethoxysilane, and dimethyldiethoxysilane; nitrogen-and sulfur-containing alkoxysilane compounds such as 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, mercaptomethyltrimethoxysilane, mercaptomethyltriethoxysilane, 3-ureidopropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, and N- (3-cyclohexylamino) propyltrimethoxysilane; epoxy group-containing silane compounds such as 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 2- (3, 4-epoxycyclohexyl) ethyltriethoxysilane, and 2- (3, 4-epoxycyclohexyl) ethyltrimethoxysilane; and unsaturated bond-containing alkoxysilane compounds such as 3- (meth) acryloyloxypropyltrimethoxysilane, 3- (meth) acryloyloxypropylmethyldimethoxysilane, 3- (meth) acryloyloxypropylmethyldiethoxysilane, vinyltrimethoxysilane and p-vinyltrimethoxysilane. The hydrolyzable silane compound may be used alone or in combination of two or more of these. In the present specification, "(meth) acryloyl group" means "acryloyl group" and "methacryloyl group".

The hydrolysis and condensation reaction is carried out by reacting one or two or more of the silane compounds described above with water, preferably in the presence of an appropriate catalyst and an organic solvent. The proportion of water used in the reaction is preferably 1 to 30 moles based on 1 mole of the silane compound (total amount). Examples of the catalyst to be used include acids, alkali metal compounds, organic bases (for example, triethylamine, tetramethylammonium hydroxide, etc.), titanium compounds, zirconium compounds, and the like. The amount of the catalyst to be used varies depending on the kind of the catalyst, reaction conditions such as temperature, and the like, and is appropriately set, and is preferably 0.01 to 3 times by mol based on the total amount of the silane compounds, for example. Examples of the organic solvent used include hydrocarbons, ketones, esters, ethers, and alcohols, and among these, it is preferable to use an organic solvent that is not water-soluble or hardly water-soluble. The amount of the organic solvent used is preferably 50 to 1,000 parts by mass based on 100 parts by mass of the total of the silane compounds used in the reaction.

The hydrolysis and condensation reaction are preferably carried out by heating with an oil bath or the like, for example. In this case, the heating temperature is preferably 130 ℃ or lower, and the heating time is preferably 0.5 to 12 hours. After the reaction is completed, the solvent is removed from the organic solvent layer separated from the reaction solution, whereby a polysiloxane can be obtained.

When a functional group such as a pretilt angle-imparting group or a photo-alignment group is introduced into a side chain of polyorganosiloxane, the method for synthesizing the polyorganosiloxane is not particularly limited, and examples thereof include the following methods: a method in which an epoxy group-containing silane compound or a mixture of an epoxy group-containing silane compound and another silane compound is subjected to hydrolytic condensation to synthesize an epoxy group-containing polyorganosiloxane, and the obtained epoxy group-containing polyorganosiloxane is reacted with a carboxylic acid having the functional group. The reaction of the epoxy group-containing polyorganosiloxane with the carboxylic acid can be carried out according to a known method.

The polyorganosiloxane preferably has a weight average molecular weight (Mw) in terms of polystyrene measured by GPC in the range of 500 to 100,000, more preferably in the range of 1,000 to 30,000, and still more preferably in the range of 1,000 to 20,000. When the weight average molecular weight of the polyorganosiloxane is in the above range, handling is easy in the production of the liquid crystal alignment film, and a liquid crystal alignment film having sufficient material strength and properties can be obtained.

The content ratio (total amount in the case of containing two or more kinds) of the [ P ] polymer in the liquid crystal aligning agent is preferably 60% by mass or more, and more preferably 80% by mass or more, relative to the total amount of the polymer components in the liquid crystal aligning agent. In addition, in terms of obtaining a liquid crystal element with more excellent reliability, the liquid crystal aligning agent preferably contains a [ p ] polymer, and the [ p ] polymer is at least one selected from the group consisting of polyamic acid, polyamic acid ester, and polyimide. The content ratio of the [ p ] polymer in the liquid crystal aligning agent (the total amount thereof in the case where two or more are contained) is preferably 40% by mass or more, and more preferably 60% by mass or more, relative to the total amount of the polymer components in the liquid crystal aligning agent.

At least a part of the polymer component contained in the liquid crystal aligning agent is preferably a polymer having a partial structure represented by the following formula (3).

*-L¹-R¹¹-R¹²-R¹³-R¹⁴…(3)

(in the formula (3), L¹is-O-, -CO-, -COO-)¹、-OCO-*¹、-NR¹⁵-、-NR¹⁵-CO-*¹、-CO-NR¹⁵-*¹C1-C6 alkanediyl, -O-R¹⁶-*¹or-R¹⁶-O-*¹(wherein, R¹⁵Is a hydrogen atom or a C1-10 monovalent hydrocarbon group, R¹⁶Is an alkanediyl group having 1 to 3 carbon atoms; "*¹"represents and R¹¹A bond of (c); r¹¹And R¹³Each independently is a single bond, phenylene or cycloalkylene, R¹²Is a single bond, phenylene, cycloalkylene, -R¹⁷-B¹-*²or-B¹-R¹⁷-*²(wherein, R¹⁷Is phenylene or cycloalkylene, B¹is-COO-)³、-OCO-*³Or a C1-3 alkanediyl group; "*²"represents and R¹³Bond, "" of³"represents and R¹⁷A bond of (c); r¹⁴Is hydrogen atom, fluorine atom, alkyl group having 1 to 18 carbon atoms, fluoroalkyl group having 1 to 18 carbon atoms, alkoxy group having 1 to 18 carbon atoms, fluoroalkoxy group having 1 to 18 carbon atoms, or hydrocarbon group having 17 to 51 carbon atoms and having a steroid skeleton, and may haveHaving a radical polymerizable group or a photoinitiator group; wherein, in R¹⁴When R is a hydrogen atom, a fluorine atom or a group having 1 to 3 carbon atoms¹¹、R¹²And R¹³Not all are single bonds; "+" indicates a bond)

In the formula (3), L ¹、B¹And R¹⁴The alkyl group, fluoroalkyl group, alkoxy group, and fluoroalkoxy group in (1) are preferably linear. As R¹⁴Examples of the group having a steroid skeleton of (1) include: cholestanyl, lanostanyl, and the like. R¹¹、R¹²、R¹³And R¹⁷The phenylene group of (A) is preferably a 1, 4-phenylene group, and the cycloalkylene group is preferably a 1, 4-cyclohexylene group. With respect to R¹¹And R¹³At least one of these is preferably phenylene or cycloalkylene. R¹²Preferably phenylene, cycloalkylene, -R¹⁷-B¹-*²or-B¹-R¹⁷-*². The main skeleton of the polymer having a partial structure represented by the formula (3) is not particularly limited, and is preferably [ P ]]A polymer.

The content ratio of the partial structure represented by the formula (3) in the polymer is preferably set as appropriate depending on the main chain of the polymer, and is preferably 1 to 50 mol%, more preferably 2 to 40 mol%, based on all monomer units of the polymer, from the viewpoint of sufficiently increasing the response speed of the liquid crystal.

In addition, in order to obtain a liquid crystal element in which an afterimage is less likely to occur and the response speed of liquid crystal is high, the liquid crystal aligning agent preferably contains the following polymers: the polymer has, as a polymer component, at least one selected from the group consisting of a radical polymerizable group, a photoinitiator group, a radical polymerization inhibitor group, a nitrogen-containing heterocycle (excluding an imide ring of polyimide), an amino group, and a protected amino group (hereinafter, also referred to as a "specific partial structure").

Examples of the radical polymerizable group include: (meth) acryloyl, vinyl, allyl, vinylphenyl, maleimido, vinyloxy, ethynyl, and the like. Among these, (meth) acryloyl groups are particularly preferable in terms of high reactivity.

The photoinitiator group is a group having a structure derived from a compound (photoinitiator) which generates polymerization initiating ability by light or has a photosensitizing action and can initiate polymerization of a polymerizable component by irradiation with radiation such as visible light, ultraviolet light, far ultraviolet light, electron beam, and X-ray. As the photoinitiator group, a group having a structure derived from a radical polymerization initiator that can generate radicals by light irradiation is preferable. Specifically, for example, a group having a structure derived from the following compounds and the like can be cited: acetophenone-based compounds, oxime ester-based compounds, dibenzoyl-based compounds, benzoin-based compounds, benzophenone-based compounds, alkylphenone-based compounds, or acylphosphine oxide-based compounds. Of these, the photoinitiator group is preferably a group having an acetophenone structure. When the polymer has at least one of a radical polymerizable group and a photoinitiator group, it is preferable that the polymer has these groups in a side chain.

The radical polymerization inhibitor group functions as a peroxide decomposer for deactivating a peroxide radical or hydrogen peroxide generated in response to energy such as ultraviolet light or heat, or a radical scavenger for trapping a radical intermediate during polymerization to inhibit the progress of the polymerization reaction. By incorporating such a polymer having a polymerization inhibitor group into the liquid crystal alignment film, it is possible to suppress the reaction of the photopolymerizable compound mixed into the liquid crystal layer in the PSA mode by light irradiation. The polymerization inhibitor group is preferably a group having at least one selected from the group consisting of a hindered amine structure, a hindered phenol structure and an aniline structure.

Examples of the nitrogen-containing heterocyclic ring include: pyrrole, imidazole, pyrazole, triazole, pyridine, pyrimidine, pyridazine, pyrazine, indole, benzimidazole, purine, quinoline, isoquinoline, naphthyridine, quinoxaline, phthalazine, triazine, carbazole, acridine, piperidine, piperazine, pyrrolidine, hexamethyleneimine and the like. Among them, at least one selected from the group consisting of pyridine, pyrimidine, pyrazine, piperidine, piperazine, quinoline, carbazole, and acridine is preferable.

The amino group and the protected amino group are preferably a group represented by the following formula (N-1).

[ solution 4]

(in the formula (N-1), R⁵⁰Is a hydrogen atom or a monovalent organic group; "+" is a bond to a hydrocarbon group)

In the formula (N-1), R⁵⁰The monovalent organic group (2) is preferably a monovalent hydrocarbon group or a protecting group. The monovalent hydrocarbon group preferably has 1 to 10 carbon atoms, and specific examples thereof include: straight or branched alkyl groups such as methyl, ethyl, propyl and butyl; cycloalkyl groups such as cyclohexyl; aryl groups such as phenyl and methylphenyl; aralkyl groups such as benzyl group, etc. As R⁵⁰Examples of the substituent which may be contained include: halogen atom, cyano group, alkylsilyl group, alkoxysilyl group and the like. R⁵⁰Preferably an alkyl group having 1 to 5 carbon atoms, a cyclohexyl group, a phenyl group or a benzyl group. Examples of the hydrocarbon group bonded with "+" in the formula (N-1) include: alkanediyl, cyclohexylene, phenylene, and the like.

The protecting group is preferably a group which is detached by heat, and examples thereof include: urethane-based protecting groups, amide-based protecting groups, imide-based protecting groups, sulfonamide-based protecting groups, groups represented by the following formulae (8-1) to (8-5), and the like. Among them, the protecting group is preferably a tert-butoxycarbonyl group in terms of high releasability by heat or in terms of reducing the amount of remaining deprotected portions in the film.

[ solution 5]

In (formulae (8-1) to (8-5), Ar¹¹A monovalent group having 6 to 10 carbon atoms obtained by removing one hydrogen atom from a substituted or unsubstituted aromatic ring，R⁶¹Is C1-12 alkyl, R⁶²Is methylene or ethylene; "+" indicates a bond to a nitrogen atom)

The main skeleton of the polymer having the specific partial structure is not particularly limited, and is preferably a [ P ] polymer, and more preferably a [ P ] polymer. The content ratio of the specific partial structure in the polymer (the total amount thereof in the case of containing two or more species) is preferably 5 mol%, more preferably 10 to 80 mol%, based on all monomer units of the polymer.

(solvent)

The liquid crystal aligning agent contains, as a solvent component, at least one specific solvent selected from the group of solvents (including the group of [ A ] solvent and [ B ] solvent) shown below.

Solvent group:

[ solution 6]

[ solution 7]

(in the formula (2), R²And R³Each independently being a hydrogen atom, a carbon atomA monovalent hydrocarbon group having a number of 1 to 6, or a monovalent group having "-O-" between carbon-carbon bonds of the hydrocarbon group, R²And R³Can bond with each other to form a ring structure; r⁴Alkyl group having 1 to 6 carbon atoms)

With respect to [ A ] solvent

(Compound represented by the formula (1))

With respect to the compound represented by the formula (1), R¹The monovalent hydrocarbon group having 2 to 5 carbon atoms is preferably a chain hydrocarbon group, and examples thereof include: alkyl, alkenyl and alkynyl having 2 to 5 carbon atoms. Examples of the monovalent group having "-O-" between carbon-carbon bonds in the hydrocarbon group include alkoxyalkyl groups having 2 to 5 carbon atoms.

Specific examples of these include alkyl groups having 2 to 5 carbon atoms such as: ethyl, propyl, butyl, pentyl, etc.; examples of the alkenyl group having 2 to 5 carbon atoms include: vinyl, 1-propenyl, 2-propenyl, 3-butenyl, etc.; examples of the alkynyl group having 2 to 5 carbon atoms include: ethynyl, 2-propynyl, 2-butynyl and the like; examples of the alkoxyalkyl group having 2 to 5 carbon atoms include: methoxymethyl, methoxyethyl, methoxypropyl, methoxybutyl, ethoxymethyl, ethoxyethyl and the like, and these may be linear or branched. In the group, R ¹Preferably an alkyl group or an alkoxyalkyl group having 2 to 5 carbon atoms.

Specific examples of the compound represented by the formula (1) include: n-ethyl-2-pyrrolidone, N- (N-propyl) -2-pyrrolidone, N-isopropyl-2-pyrrolidone, N- (N-butyl) -2-pyrrolidone, N- (tert-butyl) -2-pyrrolidone, N- (N-pentyl) -2-pyrrolidone, N-methoxypropyl-2-pyrrolidone, N-ethoxyethyl-2-pyrrolidone, N-methoxybutyl-2-pyrrolidone, and the like. Of these, N-ethyl-2-pyrrolidone, N- (N-pentyl) -2-pyrrolidone, N- (tert-butyl) -2-pyrrolidone, N-methoxypropyl-2-pyrrolidone can be particularly preferably used. In the compounds represented by the formula (1), one of these exemplified compounds may be used alone or two or more of these compounds may be used in combination.

(Compound represented by the formula (2))

As to the formula (2)A compound of formula (I) as R²And R³Examples of the monovalent hydrocarbon group having 1 to 6 carbon atoms include a chain hydrocarbon group having 1 to 6 carbon atoms, an alicyclic hydrocarbon group having 3 to 6 carbon atoms, and an aromatic hydrocarbon group having 5 or 6 carbon atoms. Examples of the monovalent group having "-O-" between carbon-carbon bonds of the hydrocarbon group include alkoxyalkyl groups having 2 to 6 carbon atoms.

Specific examples of the linear hydrocarbon group having 1 to 6 carbon atoms include methyl, ethyl, propyl, butyl, pentyl, hexyl, and the like, and these may be linear or branched. Examples of the alicyclic hydrocarbon group having 3 to 6 carbon atoms include cyclopentyl and cyclohexyl; examples of the aromatic hydrocarbon group include phenyl group and the like; examples of the alkoxyalkyl group having 2 to 6 carbon atoms include R¹Alkoxyalkyl groups as mentioned in (1) and the like. Further, R in the formula (2)²And R³May be the same or different from each other. In addition, R²And R³Can be bonded to R through mutual bonding²And R³The bonded nitrogen atoms together form a ring. As R²、R³Examples of the ring formed by bonding to each other include a pyrrolidine ring and a piperidine ring, and a monovalent linear hydrocarbon group such as a methyl group may be bonded to these rings.

R²And R³Preferably a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, more preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and still more preferably a hydrogen atom or a methyl group.

As R⁴The C1-C6 alkyl group of (2) is listed as R²And R³The alkyl group having 1 to 6 carbon atoms. Preferably an alkyl group having 1 to 4 carbon atoms, and more preferably a methyl group or an ethyl group.

Specific examples of the compound represented by the formula (2) include: 3-butoxy-N, N-dimethylpropionamide (3-butoxy-N, N-dimethyl propanamide), 3-methoxy-N, N-dimethylpropionamide, 3-hexyloxy-N, N-dimethylpropionamide, isopropoxy-N-isopropyl-propionamide (isoproxy-N-isoproxyl-propioamide), N-butoxy-N-isopropyl-propionamide, and the like. The compound represented by the formula (2) may be used alone or in combination of two or more.

As [ A ]]The solvent is preferably at least one selected from the group consisting of the compound represented by the formula (1), the compound represented by the formula (2), and 1, 3-dimethyl-2-imidazolidinone, and more preferably at least one selected from the group consisting of R in the compound represented by the formula (1), from the viewpoint of further reducing the influence exerted on the interlayer insulating film 21¹The compound is at least one selected from the group consisting of an alkyl or alkoxyalkyl compound having 2 to 5 carbon atoms, 3-methoxy-N, N-dimethylpropionamide, and 1, 3-dimethyl-2-imidazolidinone, and particularly preferably at least one selected from the group consisting of N-ethyl-2-pyrrolidone, N- (N-pentyl) -2-pyrrolidone, N- (tert-butyl) -2-pyrrolidone, N-methoxypropyl-2-pyrrolidone, 3-methoxy-N, N-dimethylpropionamide, and 1, 3-dimethyl-2-imidazolidinone.

As the solvent [ B ], at least one selected from the group consisting of dipropylene glycol monomethyl ether, propylene glycol diacetate, diethylene glycol diethyl ether, diisoamyl ether, diacetone alcohol, and propylene glycol monobutyl ether is preferable in terms of further reducing the influence on the interlayer insulating film 21.

As the solvent component, only a specific solvent may be used, or a solvent other than the specific solvent may be used in combination. Examples of the other solvent include a solvent having high solubility and leveling property of the polymer (hereinafter, also referred to as "first solvent") and a solvent having good wet spreadability (hereinafter, also referred to as "second solvent").

Specific examples of these include the following first solvents: n-methyl-2-pyrrolidone, γ -butyrolactone, γ -butyrolactam, N-dimethylformamide, N-dimethylacetamide, 4-hydroxy-4-methyl-2-pentanone, ethylene carbonate, propylene carbonate, or the like;

examples of the second solvent include: ethylene glycol monomethyl ether, butyl lactate, butyl acetate, methyl methoxypropionate, ethyl ethoxypropionate, ethylene glycol methyl ether, ethylene glycol ethyl ether, ethylene glycol-n-propyl ether, ethylene glycol-isopropyl ether, ethylene glycol-n-butyl ether (butyl cellosolve), ethylene glycol dimethyl ether, ethylene glycol ethyl ether acetate, diethylene glycol dimethyl ether, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol diethyl ether acetate, isoamyl propionate, isoamyl isobutyrate, and the like. As the other solvent, one of the solvents mentioned above may be used alone, or two or more of the solvents may be used in combination.

In the preparation of the liquid crystal aligning agent, only either of the [ a ] solvent and the [ B ] solvent can be used as the specific solvent, but at least one of the [ a ] solvent and the [ B ] solvent is preferably contained in order to suppress the influence on the interlayer insulating film 21 in a state where the liquid crystal aligning agent is in contact with the interlayer insulating film 21 when the liquid crystal alignment film is formed and to suppress the effect of elution of impurity components from the interlayer insulating film 21 to be high.

From the viewpoint of sufficiently obtaining the effect of suppressing the influence on the interlayer insulating film 21 and the effect of suppressing the elution of the impurity components from the interlayer insulating film 21 and suppressing the deposition of the polymer components, the usage ratio of [ a ] the solvent (the total amount thereof in the case of using two or more kinds) is preferably 10% by mass or more, and more preferably 20% by mass or more, relative to the total amount of the solvent contained in the liquid crystal aligning agent. In addition, from the viewpoint of obtaining the effect of improving coatability by the solvent [ B ], the upper limit of the usage ratio thereof is preferably 90 mass% or less, more preferably 80 mass% or less, with respect to the total amount of the solvent contained in the liquid crystal aligning agent. Further, the solvent [ A ] may be used singly or in combination of two or more.

From the viewpoint of suppressing the influence on the interlayer insulating film 21 and the elution of impurity components from the interlayer insulating film 21 and improving the coatability of the liquid crystal aligning agent, [ B ] the use ratio of the solvent (the total amount thereof in the case of using two or more kinds of solvents) is preferably 10% by mass or more, and more preferably 20% by mass or more, relative to the total amount of the solvent contained in the liquid crystal aligning agent. The upper limit of the use ratio is preferably 80 mass% or less, more preferably 70 mass% or less, relative to the total amount of the solvent contained in the liquid crystal aligning agent. Further, the solvent [ B ] may be used singly or in combination of two or more.

From the viewpoint of sufficiently obtaining the effect of suppressing the influence on the interlayer insulating film 21 and the effect of reducing the elution of impurity components from the interlayer insulating film 21, the use ratio of the specific solvent (the total amount of two or more solvents) is preferably 50% by mass or more, more preferably 70% by mass or more, even more preferably 90% by mass or more, and particularly preferably 95% by mass or more, with respect to the total amount of the solvents contained in the liquid crystal aligning agent.

In the case where the solvent [ a ], the solvent [ B ] and another solvent are used, the ratio of the other solvent to be used (the total amount thereof in the case where two or more solvents are used) is preferably 50% by mass or less, more preferably 30% by mass or less, even more preferably 10% by mass or less, and particularly preferably 5% by mass or less, with respect to the total amount of the solvents contained in the liquid crystal aligning agent, from the viewpoint of sufficiently obtaining the effect of the present disclosure.

The liquid crystal aligning agent is particularly preferably a liquid crystal aligning agent containing [ A ] solvent and [ B ] solvent as solvent components. In the present specification, the phrase "the solvent component includes the solvent [ a ] and the solvent [ B ]" allows the solvent [ a ] and the solvent [ B ] to be contained in an amount not to impair the effects of the present disclosure.

The liquid crystal aligning agent may contain other components in addition to the polymer component and the solvent component, as necessary. Examples of the other components include: antioxidants, metal chelate compounds, hardening accelerators, surfactants, fillers, dispersants, photosensitizers, and the like. The blending ratio of the other components may be appropriately selected depending on each compound within a range not impairing the effects of the present disclosure.

The concentration of the solid component in the liquid crystal aligning agent (the ratio of the total mass of the components other than the solvent of the liquid crystal aligning agent to the total mass of the liquid crystal aligning agent) may be appropriately selected in consideration of viscosity, volatility and the like, and is preferably in the range of 1 to 10 mass%. When the solid content concentration is less than 1% by mass, the film thickness of the coating film is too small to obtain a good liquid crystal alignment film. On the other hand, when the solid content concentration exceeds 10 mass%, the film thickness of the coating film is too large to obtain a good liquid crystal alignment film, and the viscosity of the liquid crystal alignment agent tends to increase to lower the coatability.

< radiation-sensitive resin composition >

Next, the radiation-sensitive resin composition for forming the interlayer insulating film 21 will be described in detail. The radiation-sensitive resin composition contains a [ Q ] polymer and an [ R ] sensitizer.

([ Q ] Polymer)

The [ Q ] polymer preferably contains a constituent unit having a polymerizable group. The polymerizable group of the [ Q ] polymer is preferably at least one selected from the group consisting of an oxetanyl group, (meth) acryloyl group, and a vinyl group. By having such a polymerizable group, the radiation-sensitive resin composition can be easily cured, and a favorable interlayer insulating film 21 can be obtained, which is preferable in view of the above.

The main skeleton of the [ Q ] polymer is not particularly limited, and is preferably at least one selected from the group consisting of (meth) acrylic polymers, polyamic acids, polyamic acid esters, polyimides, and polyorganosiloxanes. Among these, (meth) acrylic polymers are particularly preferable. The (meth) acrylic polymer may contain only a structural unit derived from a monomer having a (meth) acryloyl group, or may contain a structural unit derived from a monomer having a (meth) acryloyl group and a structural unit derived from another monomer different from the monomer having a (meth) acryloyl group. The content ratio of the structural unit derived from another monomer in the (meth) acrylic polymer is preferably 50 mol% or less, more preferably 40 mol% or less, and still more preferably 30 mol% or less.

Specifically, the [ Q ] polymer is preferably a polymer containing a first structural unit having an acidic group, a second structural unit having an oxetanyl group or an oxetanyl group, and a third structural unit having a main chain structure different from that of the first structural unit and the second structural unit.

Examples of the acidic group contained in the first structural unit include: a carboxyl group, a sulfo group, a phenolic hydroxyl group, a phosphate group, a sulfonate group, a phosphonate group, a sulfonamide group, a hydroxyalkyl group in which a hydrogen atom bonded to a carbon atom is substituted with an electron-withdrawing group, and the like. Among these, a carboxyl group, a sulfo group, a phenolic hydroxyl group, a fluorine-containing alcoholic hydroxyl group, a phosphoric acid group, a sulfonic acid group, a phosphonic acid group, or a combination thereof is preferable, a carboxyl group or a phenolic hydroxyl group is more preferable, and a carboxyl group is particularly preferable in terms of alkali developability.

The first structural unit is preferably a structural unit derived from at least one compound selected from the group consisting of (meth) acrylic acid and unsaturated carboxylic acid anhydrides, and particularly preferably at least one of (meth) acrylic acid and maleic anhydride.

The content ratio of the first structural unit in the [ Q ] polymer is preferably 1 to 50 mol%, more preferably 15 to 30 mol%, based on all the structural units constituting the [ Q ] polymer. The first structural unit may be a single one, or two or more kinds may be combined.

The second structural unit is preferably a structural unit derived from at least one compound selected from the group consisting of glycidyl (meth) acrylate, 3, 4-epoxycyclohexylmethyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate glycidyl ether, and 3- (meth) acryloyloxymethyl-3-ethyloxetane.

The content ratio of the second structural unit in the [ Q ] polymer is preferably 1 to 15 mol%, more preferably 3 to 10 mol%, based on all the structural units constituting the [ Q ] polymer. The second structural unit may be a single kind or two or more kinds may be combined.

The third structural unit is not particularly limited as long as it is a structural unit derived from a monomer that forms a different main chain structure from the first structural unit and the second structural unit, and is preferably a structural unit derived from at least one compound selected from the group consisting of styrene, α -methylstyrene, 4-methylstyrene, and 4-hydroxystyrene in terms of better development adhesion and resistance to heat or a stripping solution.

The content ratio of the third structural unit in the [ Q ] polymer is preferably 25 to 80 mol%, more preferably 30 to 65 mol%, based on all the structural units constituting the [ Q ] polymer. The third structural unit may be a single one, or two or more of them may be combined.

The [ Q ] polymer may further have a structural unit other than the first structural unit, the second structural unit and the third structural unit. Examples of such a structural unit include alkyl (meth) acrylates and the like.

The [ Q ] polymer can be synthesized by a conventional method such as radical polymerization using a monomer that provides the first to third structural units. The synthesis conditions can be set as appropriate with reference to various conditions described in japanese patent laid-open publication No. 2015-92233, for example.

([ R ] photosensitizer)

As the [ R ] sensitizer, at least one selected from the group consisting of a photoradical polymerization initiator, a photoacid generator, and a photobase generator can be preferably used.

Specific examples of these include the photo radical polymerization initiators: o-acyloxime compounds, acetophenone compounds, biimidazole compounds, and the like;

examples of the photoacid generator include: oxime sulfonate compounds, onium salts, sulfonimide compounds, halogen-containing compounds, diazomethane compounds, sulfone compounds, sulfonate compounds, carboxylate compounds, quinone diazide compounds, and the like;

examples of the photobase generators include: transition metal complexes such as cobalt, o-nitrobenzyl amino acid esters, α -dimethyl-3, 5-dimethoxybenzyl amino acid esters, acyloxyimino compounds, and the like.

The ratio of the photosensitizer used varies depending on the kind of the compound used. For example, in the case of the photo radical polymerization initiator, it is preferably 1 to 40 parts by mass, more preferably 5 to 30 parts by mass, per 100 parts by mass of the [ Q ] polymer.

The proportion of the photoacid generator used is preferably 0.1 to 50 parts by mass, more preferably 1 to 30 parts by mass, per 100 parts by mass of the [ Q ] polymer.

The proportion of the photoacid-base agent used is preferably 0.1 to 20 parts by mass, more preferably 1 to 10 parts by mass, per 100 parts by mass of the [ Q ] polymer.

The radiation-sensitive resin composition may further contain a curing accelerator, a polymerizable unsaturated compound, a surfactant, a storage stabilizer, and an adhesion promoter in addition to the [ Q ] polymer and the [ R ] sensitizer. These optional components may be used alone or in combination of two or more.

The radiation-sensitive resin composition can be prepared by mixing the [ Q ] polymer and the [ R ] sensitizer, and optionally other optional components. The radiation-sensitive resin composition is preferably used in a solution state by dissolving it in an appropriate solvent. Examples of the solvent include: alcohols, glycol ethers, ethylene glycol alkyl ether acetates, diethylene glycol monoalkyl ethers, diethylene glycol dialkyl ethers, dipropylene glycol dialkyl ethers, propylene glycol monoalkyl ethers, propylene glycol alkyl ether acetates, propylene glycol monoalkyl ether propionates, ketones, esters and the like.

The content of the solvent is preferably an amount such that the total concentration of the components of the radiation-sensitive resin composition excluding the solvent is 5 to 50 mass%, more preferably 10 to 40 mass%, from the viewpoint of coatability, stability, and the like of the obtained radiation-sensitive resin composition.

(method of manufacturing liquid Crystal device 10)

The liquid crystal device 10 can be manufactured by a method including the following steps a to E.

Step A: a step of forming an interlayer insulating film 21 on the substrate.

And B, step B: a step of forming the pixel electrode 19 on the interlayer insulating film 21.

Step C: and a step of forming a liquid crystal alignment film (first alignment film 32) on the pixel electrode 19 so as to be in contact with a part of the interlayer insulating film 21.

Step D: and a step of configuring a liquid crystal cell by disposing the array substrate 15 and the counter substrate 16 in opposition to each other with a liquid crystal layer containing a photopolymerizable monomer interposed therebetween.

Step E: and irradiating the liquid crystal cell with light.

In manufacturing the liquid crystal device 10 shown in fig. 1 and 2, first, the thin film transistors 14, the scanning signal lines 12, and the image signal lines 13 are formed on the transparent substrate 18 such as a glass substrate by a known method such as photolithography. Then, a radiation-sensitive resin composition for forming an interlayer insulating film is applied to the formation surface of the thin film transistor 14 and the signal line on the transparent substrate 18 to form an interlayer insulating film 21 (step a).

The method for applying the radiation-sensitive resin composition is not particularly limited, and suitable methods such as a spray method, a roll coating method, a spin coating method, a slit coating method, a bar coating method, and an inkjet coating method can be used. Among these methods, a spin coating method or a slit coating method is preferable in terms of forming a film having a uniform thickness. After the radiation-sensitive resin composition is applied, the applied surface is preferably heated (prebaked), and the coating film is exposed to light via a photomask having a predetermined pattern as necessary, and then developed and postbaked, thereby obtaining an interlayer insulating film 21 as a cured film. As various conditions for forming the interlayer insulating film 21, for example, the conditions described in japanese patent laid-open No. 2015-92233 can be adopted.

In the next step B, the pixel electrode 19 is formed on the interlayer insulating film 21 formed in step a in the transparent substrate 18. The pixel electrode 19 is formed by a known method such as sputtering to have a film thickness of 50nm to 200nm, more preferably 100nm to 150nm, such as an ITO (Indium tin Oxide) film or an Indium Zinc Oxide (IZO) film, and then patterned into a fishbone shape (also referred to as a "comb-tooth shape") by photolithography. In this way, the fishbone-shaped pixel electrode 19 is formed on the substrate to produce the array substrate 15.

Separately from the above, the color filter layer 29, an overcoat layer (not shown) and the common electrode 31 are sequentially formed on the transparent substrate 28 such as a glass substrate by a known method such as photolithography to produce the counter substrate 16.

In the next step C, first, a liquid crystal alignment agent is applied to the substrate on which the electrode is formed, and preferably, the coated surface is heated, thereby forming a coating film on the substrate. The liquid crystal aligning agent is preferably applied to the substrate by a lithographic method, a spin coating method, a roll coater method, a flexographic printing method, or an inkjet printing method on the electrode-forming surface. After the liquid crystal aligning agent is applied, preheating (prebaking) is preferably performed for the purpose of preventing dripping of the applied liquid crystal aligning agent, and the like. The pre-baking temperature is preferably 30-200 ℃, and the pre-baking time is preferably 0.25-10 minutes. Thereafter, a calcination (post-baking) step is carried out for the purpose of completely removing the solvent and, if necessary, thermally imidizing the amic acid structure present in the polymer. The calcination temperature (post-baking temperature) in this case is preferably 80 to 300 ℃, and the post-baking time is preferably 5 to 200 minutes. The thickness of the film thus formed is preferably 0.001 to 1 μm. After the liquid crystal alignment agent is applied to the substrate, the organic solvent is removed, thereby forming a liquid crystal alignment film or a coating film to be the liquid crystal alignment film.

Here, a liquid crystal aligning agent is applied to the interlayer insulating film 21 on the electrode forming surface of the substrate on which the pattern electrode (pixel electrode 19) having a large number of slit portions 19c is formed. Therefore, the liquid crystal aligning agent comes into contact with the interlayer insulating film 21 through the opening of the slit portion 19 c. The liquid crystal alignment film (first alignment film 32) formed on the substrate is in contact with the interlayer insulating film 21 via the slit portion 19c in the display region of the liquid crystal device 10.

The coating film formed as described above may be used as it is as a liquid crystal alignment film, or may be subjected to a treatment (alignment treatment) for imparting liquid crystal alignment ability. As the orientation treatment, there can be mentioned: rubbing treatment in which a coating film is rubbed in a certain direction by a roller around which a cloth containing fibers such as nylon (nylon), rayon (rayon), or cotton (cotton) is wound, photo-alignment treatment in which a coating film formed on a substrate is irradiated with light using a liquid crystal aligning agent to impart liquid crystal aligning ability to the coating film, and the like.

In the next step D, the array substrate 15 on which the interlayer insulating film 21, the pixel electrode 19, and the first alignment film 32 are sequentially formed and the counter substrate 16 on which the common electrode 31 and the second alignment film 33 are sequentially formed are arranged so that the alignment film forming surfaces thereof face each other. A liquid crystal layer 17 in which a photopolymerizable monomer is mixed is disposed between the array substrate 15 and the counter substrate 16, thereby constructing a liquid crystal cell.

The liquid crystal layer 17 is formed by, for example: a method of dropping or coating a liquid crystal composition on One of the substrates coated with the sealant and then attaching the other substrate (One Drop Filling (ODF) method); or a method in which the peripheral edges of a pair of substrates arranged to face each other with a cell gap therebetween are bonded together with a sealant, and a liquid crystal composition is injected and filled into the cell gap surrounded by the substrate surface and the sealant, and then the injection hole is sealed. It is preferable that the obtained liquid crystal cell is further subjected to an annealing treatment of heating to a temperature at which the liquid crystal to be used becomes an isotropic phase and then slowly cooling to room temperature, thereby removing the flow alignment at the time of filling the liquid crystal.

As the photopolymerizable monomer, a compound having two or more (meth) acryloyl groups can be preferably used in terms of high polymerizability by light. Specific examples thereof include: di (meth) acrylate having a biphenyl structure, di (meth) acrylate having a phenyl-cyclohexyl structure, di (meth) acrylate having a 2, 2-diphenylpropane structure, di (meth) acrylate having a diphenylmethane structure, di-thio (meth) acrylate having a diphenylsulfide structure, and the like. The blending ratio of the photopolymerizable monomer is preferably 0.1 to 0.5 mass% based on the total amount of the liquid crystal composition used for forming the liquid crystal layer 17. The photopolymerizable monomers may be used alone or in combination of two or more.

In the next step E, the liquid crystal cell obtained in step B is subjected to light irradiation. The light irradiation to the liquid crystal cell may be performed in a state where no voltage is applied between the electrodes, in a state where a predetermined voltage that does not drive the liquid crystal molecules in the liquid crystal layer 17 is applied, or in a state where a predetermined voltage that can drive the liquid crystal molecules is applied between the electrodes. Preferably, the light irradiation is performed in a state where a voltage is applied between electrodes provided in the pair of substrates. The applied voltage may be, for example, 5V to 50V dc or ac. As the light to be irradiated, for example, ultraviolet rays and visible rays including light having a wavelength of 150nm to 800nm, preferably ultraviolet rays including light having a wavelength of 300nm to 400nm, can be used. When the radiation used is linearly polarized light or partially polarized light, the irradiation direction of light may be from a direction perpendicular to the substrate surface, from an oblique direction, or a combination thereof. When unpolarized radiation is irradiated, the irradiation direction is an oblique direction.

Examples of the light source for irradiating light include a low-pressure mercury lamp, a high-pressure mercury lamp, a deuterium lamp, a metal halide lamp, an argon resonance lamp, a xenon lamp, and an excimer laser. The ultraviolet light in the preferred wavelength range can be obtained by means of a combination of a light source and, for example, a filter diffraction grating. The dose of light irradiation is preferably 1,000J/m ²～200,000J/m²More preferably 1,000J/m²～100,000J/m²。

Then, a polarizing plate 36 and a polarizing plate 37 were attached to the outer surface of the liquid crystal cell, thereby obtaining a liquid crystal device 10. Examples of the

polarizing plates

36 and 37 include: a polarizing plate in which a polarizing film called "H film" in which iodine is absorbed while polyvinyl alcohol is stretched and oriented, or a polarizing plate including the H film itself is sandwiched between cellulose acetate protective films.

In the present embodiment, the first alignment film 32 is formed using a liquid crystal aligning agent containing a specific solvent as a solvent component. Thus, even when the first alignment film 32 is in contact with the interlayer insulating film 21 via the slit 19c, the liquid crystal device 10 having excellent reliability can be obtained. The reason why such an effect is obtained is not clear, but it is considered that, as one reason, the specific solvent used in the preparation of the liquid crystal aligning agent has a small influence on the interlayer insulating film 21, and thus the performance degradation of the interlayer insulating film 21 is suppressed. In particular, in the PSA technology, in order to improve the response characteristics in the MVA mode, for example, a micro-stripe-shaped electrode pattern of several μm is formed. When such a fine electrode pattern is formed on the substrate, it is considered that when the interlayer insulating film 21 swells due to contact between the liquid crystal alignment agent and the interlayer insulating film 21 and the film thickness slightly changes, the pixel electrode 19 is likely to be deformed and the device performance is likely to be lowered. In this respect, it is presumed that the influence on the pixel electrode 19 can be reduced as much as possible by suppressing swelling of the interlayer insulating film 21 by the specific solvent, and thus the deterioration of the device performance can be sufficiently suppressed. It is also presumed that elution of impurity components from the interlayer insulating film 21 to the liquid crystal aligning agent can be suppressed in a state where the liquid crystal aligning agent is in contact with the interlayer insulating film 21, whereby deterioration of the device performance can be sufficiently suppressed.

(second embodiment)

Next, the second embodiment will be described focusing on differences from the first embodiment. The present embodiment is different from the first embodiment in that a color filter layer is provided on the array substrate 15.

Fig. 3 is a cross-sectional view schematically showing a part of the element structure of the second embodiment. The liquid crystal device 10 shown in fig. 3 has a structure in which the array substrate 15 and the counter substrate 16 are disposed to face each other with the liquid crystal layer 17 interposed therebetween, as in the liquid crystal device of the first embodiment. The array substrate 15 has TFTs 14 and a color filter layer 29 including a coloring pattern 29a and an interlayer insulating film 29b on a transparent substrate 18. The colored pattern 29a includes subpixels colored in red (R), green (G), and blue (B), and is produced by a known method such as photolithography. The interlayer insulating film 29b is formed using the radiation-sensitive resin composition described in the first embodiment. The interlayer insulating film 29b is provided for the purpose of protecting the colored pattern 29a and forming the pixel electrode 19 exhibiting excellent characteristics. The pixel electrode 19 is disposed on the interlayer insulating film 29 b.

In this case, since the first alignment film 32 is formed on the electrode formation surface of the substrate on which the fishbone-shaped pattern electrode (pixel electrode 19) is formed on the interlayer insulating film 29b, the first alignment film 32 comes into contact with the interlayer insulating film 29b in the slit portion 19 c. In this regard, by forming the first alignment film 32 using the liquid crystal aligning agent, the liquid crystal device 10 excellent in reliability can be obtained.

(other embodiments)

In the first embodiment, the pixel electrode 19 on the array substrate 15 side is used as the pattern electrode, and the interlayer insulating film 21 and the first alignment film 32 are in contact with each other in the slit portion 19c, but the pattern electrode and the interlayer insulating film may be provided on the counter electrode 16 side, and the pattern electrode and the interlayer insulating film may be in contact with each other in the slit portion.

The liquid crystal device 10 of the present invention described in detail above can be effectively applied to various applications, for example, various display devices and light control devices for clocks, portable games, word processors, notebook Personal computers, car navigation systems, camcorders, Personal Digital Assistants (PDAs), Digital cameras, mobile phones, smart phones, various monitors, liquid crystal televisions, information displays, and the like.

Examples

Hereinafter, embodiments of the present invention will be described in more detail based on examples, but the present invention is not to be construed as being limited by the following examples.

In the following examples, the imidization ratio of polyimide in the polymer solution, the solution viscosity of the polymer solution, the weight average molecular weight of the polymer, and the epoxy equivalent weight were measured by the following methods.

[ imidization ratio of polyimide ]

Adding polyimide solution into pure water, drying the obtained precipitate at room temperature under reduced pressure, dissolving in deuterated dimethyl sulfoxide, measuring at room temperature with tetramethylsilane as reference substance¹H-Nuclear Magnetic Resonance (NMR). According to the obtained¹H-NMR spectrum, the imidization rate [% ] was determined by the following numerical formula (1)]。

Imidization rate [% ]]＝(1-(A¹/(A²×α)))×100…(1)

(in the numerical formula (1), A¹To be at a chemical shift of 10ppnPeak area of nearby NH group-derived protons, A²α is the ratio of the number of other protons in the precursor (polyamic acid) of the polymer to one proton of the NH group, which is the peak area derived from the other protons

[ weight average molecular weight of Polymer ]

The weight average molecular weight is a polystyrene equivalent value determined by gel permeation chromatography under the following conditions.

Pipe column: TSKgelGRCXLII manufactured by Tosoh corporation

Solvent: tetrahydrofuran (THF)

Temperature: 40 deg.C

Pressure: 68kgf/cm²

[ epoxy equivalent ]

The epoxy equivalent is measured by the methyl ethyl ketone hydrochloride method described in Japanese Industrial Standards (JIS) C2105.

The abbreviations used in the following examples are shown. In the following, the compound represented by the formula X may be simply referred to as "compound X".

[ solution 8]

[ solution 9]

[ solution 10]

[ solution 11]

1. Preparation of radiation-sensitive resin composition (for Forming interlayer insulating film)

(1) [ Q ] Synthesis of Polymer

Synthetic example 1: synthesis of Polymer (Q-1)

In a flask equipped with a cooling tube and a stirrer, 8 parts by mass of 2,2' -azobis (2, 4-dimethylvaleronitrile) and 220 parts by mass of diethylene glycol methyl ethyl ether were charged. Then, 25 parts by mass of methacrylic acid, 45 parts by mass of 3, 4-epoxycyclohexyl methacrylate, and 30 parts by mass of styrene were charged, and after nitrogen substitution, polymerization was carried out by raising the temperature of the solution to 70 ℃ while gradually stirring, and maintaining the temperature for 5 hours, thereby obtaining a solution containing the polymer (Q-1). The Mw of the polymer (Q-1) was 8000.

[ Synthesis example 2: synthesis of Polymer (Q-2)

In a flask equipped with a cooling tube and a stirrer, 8 parts by mass of 2,2' -azobis (2, 4-dimethylvaleronitrile) and 220 parts by mass of diethylene glycol methyl ethyl ether were charged. Then, 15 parts by mass of methacrylic acid, 40 parts by mass of 3, 4-epoxycyclohexyl methacrylate, 20 parts by mass of styrene, 15 parts by mass of tetrahydrofurfuryl methacrylate, and 10 parts by mass of n-lauryl methacrylate were charged, and after nitrogen substitution, polymerization was carried out by raising the temperature of the solution to 70 ℃ while gradually stirring, and maintaining the temperature for 5 hours, thereby obtaining a solution containing the polymer (Q-2). The Mw of the polymer (Q-2) was 8000.

[ Synthesis example 3: synthesis of Polymer (Q-3)

In a flask equipped with a cooling tube and a stirrer, 8 parts by mass of 2,2' -azobis (2, 4-dimethylvaleronitrile) and 220 parts by mass of diethylene glycol methyl ethyl ether were charged. Then, 40 parts by mass of glycidyl methacrylate, 20 parts by mass of 4- (. alpha. -hydroxyhexafluoroisopropyl) styrene, 10 parts by mass of styrene, and 30 parts by mass of N-cyclohexylmaleimide were charged, and after nitrogen substitution, polymerization was carried out while gradually stirring while raising the temperature of the solution to 70 ℃ and maintaining the temperature for 5 hours, thereby obtaining a solution containing the polymer (Q-3). The Mw of the polymer (Q-3) was 8000.

(2) Preparation of radiation-sensitive resin composition

[ preparation example 1]

To the solution containing the polymer (Q-1) obtained in the synthesis example 1 (the amount of the polymer (Q-1) corresponding to 100 parts by mass (solid content)) was added 20 parts by mass of 1, 2-octanedione 1- [4- (phenylthio) -2- (O-benzoyloxime) ] (gorgeous good solids (Irgacure) (registered trademark) OXE01 manufactured by BASF corporation), and further 100 parts by mass of a mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate (KAYARAD (registered trademark) DPHA, manufactured by japan chemicals) was added and mixed. Diethylene glycol ethyl methyl ether was added to a solid content concentration of 30 mass% and dissolved, and then filtered through a membrane filter having a pore size of 0.2 μm to prepare a radiation-sensitive resin composition (V-1).

[ preparation examples 2 to 4]

Radiation-sensitive resin compositions (V-2) to (V-4) were prepared in the same manner as in preparation example 1 except that the formulation compositions were changed as shown in Table 1 below. In table 1 below, "-" means that the above-mentioned component was not blended (the same applies to the following table).

[ Table 1]

In table 1, the abbreviations of the compounds are as follows.

R-1: 1, 2-octanedione 1- [4- (phenylthio) -2- (O-benzoyloxime) ] (manufactured by BASF corporation, Irgacure (registered trademark) OXE01)

R-2: condensate of 4,4' - [1- [4- [1- [ 4-hydroxyphenyl ] -1-methylethyl ] phenyl ] ethylene ] bisphenol (1.0 mol) and 1, 2-naphthoquinonediazide-5-sulfonyl chloride (2.0 mol)

U-1: DPHA (registered trademark) a mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate (manufactured by Nippon Chemicals Co., Ltd.)

2. Synthesis of Polymer (for liquid Crystal alignment agent)

[ Synthesis example 5: synthesis of Polymer (PI-1)

100 parts by mole of 2,3, 5-tricarboxycyclopentylacetic acid dianhydride as tetracarboxylic acid dianhydride, 20 parts by mole of cholestanoxy-2, 4-diaminobenzene as diamine, 50 parts by mole of 3, 5-diaminobenzoic acid, and 30 parts by mole of compound (d-8) were dissolved in N-methyl-2-pyrrolidone (NMP) and reacted at room temperature for 6 hours to obtain a solution containing 20 mass% of polyamic acid. Then, pyridine and acetic anhydride were added to the obtained polyamic acid solution, and chemical imidization was performed. The reaction solution after chemical imidization was concentrated and prepared with NMP so that the concentration became 10 mass%. The imidization ratio of the obtained polyimide (assuming that it is the polymer (PI-1)) was about 75%.

Synthesis examples 6 to 8

Polyimides (polymers (PI-2) to (PI-4)) were synthesized in the same manner as in Synthesis example 5 except that the kinds and amounts of tetracarboxylic dianhydride and diamine used were changed as shown in Table 2 below. In table 2, the values in parentheses represent the use ratio [ molar parts ] of each compound relative to 100 molar parts of the total tetracarboxylic dianhydrides used in the synthesis of the polymer.

[ Synthesis example 9: synthesis of Polymer (PAA-1) ]

70 parts by mole of 2,3, 5-tricarboxycyclopentylacetic acid dianhydride and 30 parts by mole of 1,2,3, 4-cyclobutanetetracarboxylic dianhydride as tetracarboxylic dianhydride, and 20 parts by mole of cholestanoxy-2, 4-diaminobenzene as diamine, 30 parts by mole of the compound (d-12), 40 parts by mole of 4,4' -diaminodiphenylmethane, and 10 parts by mole of 4,4' - [4,4' -propane-1, 3-diylbis (piperidine-1, 4-diyl) ] diphenylamine were dissolved in NMP and reacted at room temperature for 6 hours to obtain a solution containing 20 mass% of polyamic acid. The polyamic acid obtained here was set to be a polymer (PAA-1).

[ Synthesis example 10]

Polyamic acid (which was referred to as polymer (PAA-2)) was synthesized in the same manner as in synthesis example 9, except that the kinds and amounts of tetracarboxylic dianhydride and diamine used were changed as described in table 2 below.

[ Table 2]

[ Synthesis example 11]

100g of the compound (s-1), 500g of methyl isobutyl ketone, and 10g of triethylamine were charged into a reaction vessel equipped with a stirrer, a thermometer, a dropping funnel, and a reflux condenser, and mixed at room temperature. Then, after taking 30 minutes, 100g of deionized water was dropped from the dropping funnel, and the reaction was carried out at 80 ℃ for 6 hours under reflux with stirring. After the reaction was completed, the organic layer was taken out, washed with a 0.2 mass% ammonium nitrate aqueous solution until the washed water became neutral, and then the solvent and water were distilled off under reduced pressure to obtain a reactive polyorganosiloxane (ESSQ-1) as a viscous transparent liquid. The reactive polyorganosiloxane is subjected to¹As a result of H-NMR analysis, it was confirmed that a peak based on an epoxy group was obtained in the vicinity of a chemical shift (δ) of 3.2ppm, and a side reaction of the epoxy group did not occur during the reaction. The reactive polyorganosiloxane (ESSQ-1) obtained had a weight-average molecular weight Mw of 3000 and an epoxy equivalent of 190 g/mole.

Synthesis examples 12 and 13

Reactive polyorganosiloxanes (polymer (ESSQ-2) and polymer (ESSQ-3)) were synthesized in the same manner as in synthesis example 11, except that the kind and amount of the monomer used were changed as described in table 3 below. In table 3, the values in parentheses represent the use ratio [ parts by mole ] of each compound relative to 100 parts by mole of the total monomers used for the synthesis of the polymer.

[ Table 3]

[ Synthesis example 14]

A500 mL three-necked flask was charged with 10.0g of reactive polyorganosiloxane (ESSQ-1), 300g of methyl isobutyl ketone as a solvent, 16g of the compounds (c-1) and (c-3) as modifying components, and 0.10g of UCAT 18X (trade name, manufactured by Santo-Apro) (Co., Ltd.) as a catalyst, and the mixture was stirred at 100 ℃ for 48 hours to effect a reaction. After completion of the reaction, ethyl acetate was added to the reaction mixture, the obtained solution was washed with water 3 times, the organic layer was dried over magnesium sulfate, and the solvent was distilled off, whereby 75g of a polymerizable group-containing polyorganosiloxane (PSQ-1) was obtained. The weight average molecular weight Mw of the obtained polymer was 6000.

Synthesis examples 15 and 16

Polyorganosiloxanes containing a polymerizable group (polymer (PSQ-2) and polymer (PSQ-3)) were synthesized in the same manner as in synthesis example 14, except that the kinds and amounts of the reactive polyorganosiloxane and the modifying component used were changed as described in table 4 below. In table 4, the values in parentheses represent the use ratio [ molar parts ] of each compound relative to 100 molar parts of the total monomers used in the synthesis of the polymer.

[ Table 4]

3. Liquid crystal aligning agent and evaluation of liquid crystal display element

[ example 1]

(1) Preparation of liquid crystal aligning agent

In a solution containing a polymer (PI-1) as a polymer component, to obtain a polymer (PI-1): polymer (PSQ-1) ═ 95: 5 (mass ratio), and then NEP, Diethylene Glycol Diethyl Ether (DEDG) and Diacetone Alcohol (DAA) as solvents were added thereto and sufficiently stirred to prepare a solution having a solvent composition of NEP: DEDG: DAA 50: 30: 20 (mass ratio) and a solid content concentration of 6.5 mass%. The solution was filtered using a filter having a pore size of 1 μm, thereby preparing a liquid crystal aligning agent (W-1).

(2) Preparation of liquid Crystal composition (LC-1)

A liquid crystal composition (LC-1) was obtained by adding and mixing a compound represented by the following formula (RM-1) to 10g of nematic liquid crystal (MLC-6608, Merck) so as to be 0.3 mass% based on the total amount of all the components of the liquid crystal composition.

[ solution 12]

(3) Manufacture of liquid crystal display element

The radiation-sensitive resin composition (V-1) was applied to a glass substrate ("Corning 7059" (manufactured by Corning corporation)) using a spinner, and then prebaked in a clean oven at 90 ℃ for 10 minutes to form a coating film having a film thickness of 2.0 μm on each glass substrate. Then, 100mJ of UV light was irradiated through the pattern mask using a UV (ultraviolet) exposure machine (TOPCON Deep ultraviolet (TOPCON Deep-UV) exposure machine TME-400 PRJ). Then, a development treatment was performed at 25 ℃ for 100 seconds by a liquid coating method using a tetramethylammonium hydroxide aqueous solution (developer) having a concentration of 2.38 mass%. After the development treatment, the coating film was washed with running water with ultrapure water for 1 minute and dried to form a patterned coating film on the substrate, and then the substrate was heated in an oven at 230 ℃ for 30 minutes (post-baking) to be cured. Next, using a PLA-501F exposure machine (extra-high pressure mercury lamp) made by Canon (stock), 500J/m was set without passing through a photomask ²The exposure amount of (2) is an amount for exposing the entire surface of each coating film. Then, the resultant was post-baked at 230 ℃ for 30 minutes to cure each coating film, thereby forming an interlayer insulating film.

Next, an ITO electrode patterned into a fishbone shape was formed on the glass substrate on which the interlayer insulating film was formed. In the present example, the electrode pattern of the ITO electrode was formed into a fishbone shape having a line/space of 3.5 μm/3.5 μm. Fig. 4 shows an electrode pattern of the ITO electrode used here. In addition, a glass substrate including an ITO electrode having no pattern was prepared by performing the same operation. In the pair of substrates, 3.5 μm pillar spacers were formed on the electrode-side surfaces of the glass substrates including the ITO electrodes without patterns.

Next, after a liquid crystal aligning agent (W-1) was spin-coated on each electrode-forming surface of the pair of substrates, the substrates were heated (pre-baked) on a hot plate at 80 ℃ for 1 minute to remove the solvent, and then heated (post-baked) on a hot plate at 230 ℃ for 15 minutes to form a coating film having an average film thickness of 100 nm. The coating film was subjected to ultrasonic cleaning in ultrapure water for 1 minute and then dried in a clean oven at 100 ℃ for 10 minutes, thereby obtaining a pair of substrates having liquid crystal alignment films.

Then, an epoxy resin adhesive containing zirconia balls having a diameter of 5.5 μm was applied to the outer edge of the ITO surface of the glass substrate including the patterned ITO electrode, and then 6 dots (2 dots in the vertical direction × 3 dots in the horizontal direction, the interval between the dots was 10mm in the vertical direction and the horizontal direction, and the amount of application of each dot was 0.6mg) of a liquid crystal composition (LC-1) was dropped onto the inner surface of the epoxy resin adhesive. The substrate and the other glass substrate are superposed and pressed so as to face each other, and the adhesive is cured to produce a liquid crystal cell. The obtained liquid crystal cell was irradiated with ultraviolet rays and annealed in accordance with "PSA process-1" described later, thereby producing a liquid crystal cell for evaluation.

(PSA Process-1)

In the liquid crystal cell, an alternating current 20Vpp having a frequency of 60Hz was applied between the electrodes, and 80mW of ultraviolet light was irradiated for 50 seconds using an ultraviolet irradiation apparatus using a metal halide lamp as a light source in a state where the liquid crystal was driven. Then, an ultraviolet irradiation apparatus using a metal halide lamp as a light source was used to irradiate ultraviolet rays of 3.5mW for 30 minutes in a state where no voltage was applied. Finally, the liquid crystal cell was placed in a clean oven at 120 ℃ for 10 minutes to perform annealing. The irradiation dose is a value measured by using a light meter measured with reference to a wavelength of 365 nm.

(4) Evaluation of Voltage Holding Ratio (VHR)

The liquid crystal cell for evaluation manufactured in (3) was placed in a thermostatic bath, a voltage of 5V was applied at 60 ℃ for 60 microseconds and a span of 167 milliseconds, and then a Voltage Holding Ratio (VHR) after 167 milliseconds from the release of the application was measured using "VHR-1" manufactured by Toyo Technica. In this case, the case where VHR was 96% or more was evaluated as "very good" (x), the case where VHR was 93% or more and less than 96% was evaluated as "good" (o), the case where VHR was 90% or more and less than 93% was evaluated as "acceptable (Δ)", and the case where VHR was 90% or less was evaluated as "poor (x)". As a result, in the above example, VHR was 97%, which is an evaluation of "very good (circleincircle)".

Examples 2 to 22, comparative examples 1 and 2

Liquid crystal aligning agents were prepared by the same procedure as described above except that the kinds and amounts of the polymer and the solvent used were changed as described in table 5 below. In addition, except for the aspect in which the radiation-sensitive resin composition used for the preparation of the interlayer insulating film was changed to the composition shown in table 5 below and the aspect in which the liquid crystal alignment film was prepared using the liquid crystal alignment agent prepared in each example, a liquid crystal cell for evaluation was produced in the same manner as described above, and the obtained liquid crystal cell for evaluation was used to evaluate the voltage holding ratio. The results are shown in table 5 below.

[ Table 5]

In table 5, the numerical values in parentheses in the polymer column represent the blending ratios [ parts by mass ] of the respective polymers with respect to 100 parts by mass of the total of the polymer components used in the preparation of the liquid crystal aligning agent. The numerical values in the solvent composition column indicate the blending ratio [ parts by mass ] of each compound to 100 parts by mass of the solvent used for preparing the liquid crystal aligning agent as a whole. The abbreviation of the solvent is as follows (the same applies to table 6 below).

NMP: n-methyl-2-pyrrolidone

NEP: n-ethyl-2-pyrrolidone

DMI: 1, 3-dimethyl-2-imidazolidinone

EQM: 3-methoxy-N, N-dimethylpropionamide

BC: butyl cellosolve

DEDG: diethylene glycol diethyl ether

PGDAc: propylene glycol diacetate

DPM: dipropylene glycol monomethyl ether

DAA: diacetone alcohol

PG: propylene glycol monobutyl ether

DIPE: diisoamyl ether

As shown in table 5, in examples 1 to 22 in which liquid crystal alignment films were formed using a liquid crystal alignment agent containing a specific solvent, liquid crystal display elements having superior reliability as compared with comparative examples 1 and 2 in which liquid crystal alignment films were formed using a liquid crystal alignment agent not containing a specific solvent were obtained. Of these, examples 1 to 18 using the liquid crystal aligning agent containing the solvent [ A ] and the solvent [ B ] are particularly excellent for evaluation of "very good".

Further, in examples 1 to 22, liquid crystal display elements were manufactured and evaluated in the same manner as described above, except that the pattern of the ITO electrode included in the glass substrate was changed to the pattern shown in fig. 5, and as a result, the same effects as described above were obtained in any of the examples.

[ example 23]

(1) Evaluation of ITO Wiring deformation

N-ethyl-2-pyrrolidone (NEP) and diethylene glycol Diethyl Ether (DEDG) were mixed and stirred thoroughly to prepare a solvent composition of NEP: DEDG is 50: 50 (mass ratio) of solvent (Z-1).

In addition, a glass substrate provided with a pattern electrode including ITO on an interlayer insulating film was prepared by performing the same operation as in (3) of the above-described example 1. The glass substrate was immersed in a solvent (Z-1) for evaluation at 80 ℃ for 30 minutes, and the degree of swelling of the interlayer insulating film and the degree of deformation of the ITO electrode were evaluated by the following criteria. In the case of contact with a solvent component of the liquid crystal aligning agent, the smaller the swelling of the interlayer insulating film and the smaller the deformation of the electrode, the smaller the influence of the solvent on the interlayer insulating film and the ITO electrode, and the more reliable the liquid crystal element can be secured, and therefore, the solvent is preferable as a solvent of the liquid crystal aligning agent. As a result, the example was evaluated as "A".

(evaluation criteria)

A: no swelling of interlayer insulating film and no electrode abnormality

B: swelling of the interlayer insulating film was observed, but the electrode was not abnormal

C: slight abnormality such as electrode deformation due to swelling of interlayer insulating film

D: the swelling of the interlayer insulating film causes serious abnormality such as disconnection of the electrode

Examples 24 to 44, comparative examples 3 and 4

The same operations as described above were performed except that the solvent composition and the type of radiation-sensitive resin composition used were changed as shown in table 6 below, and ITO wiring deformation was evaluated for each solvent. The results are shown in table 6 below.

[ Table 6]

From the results shown in table 6, in examples 23 to 44 in which the specific solvent was used, swelling of the interlayer insulating film was not observed, or even if swelling occurred, the degree of swelling was small and no abnormality of the electrode was observed. From these results, it is found that, even when a liquid crystal alignment film is formed on a fine stripe-shaped electrode pattern in a specific solvent, the shape of the electrode is not easily changed, and the reliability of the liquid crystal element can be secured.

Claims

1. A method for manufacturing a liquid crystal element including a pair of substrates disposed to face each other, a liquid crystal layer disposed between the pair of substrates, and a pair of electrodes, wherein

At least one of the pair of electrodes is a pattern electrode having a plurality of openings,

the method for manufacturing the liquid crystal element includes: a step of forming an interlayer insulating film on at least one of the pair of substrates;

a step of forming the pattern electrode on the interlayer insulating film; and

a step of forming a liquid crystal alignment film on the pattern electrode so as to be in contact with at least a part of the interlayer insulating film,

forming the liquid crystal alignment film using a liquid crystal aligning agent containing a polymer component and at least one solvent selected from a group of solvents shown below,

solvent group:

a, solvent A: a compound represented by the following formula (1), a compound represented by the following formula (2), N, 2-trimethylpropanamide, and 1, 3-dimethyl-2-imidazolidinone;

b, solvent: dipropylene glycol monomethyl ether, dipropylene glycol dimethyl ether, diethylene glycol monoethyl ether, 4-methoxy-4-methyl-2-pentanone, 4-hydroxy-2-butanone, 2-methyl-2-hexanol, 2, 6-dimethyl-4-heptanol, diisobutyl ketone, propylene glycol diacetate, diethylene glycol diethyl ether, diisoamyl ether, diacetone alcohol, and propylene glycol monobutyl ether;

in the formula (1), R¹A monovalent hydrocarbon group having 2 to 5 carbon atoms or a monovalent group having "-O-" between carbon-carbon bonds in the hydrocarbon group;

In the formula (2), R²And R³Each independently represents a hydrogen atom, a monovalent hydrocarbon group having 1 to 6 carbon atoms, or a monovalent group having "-O-" between carbon-carbon bonds of the hydrocarbon group, R²And R³Can bond with each other to form a ring structure; r⁴An alkyl group having 1 to 6 carbon atoms,

wherein the interlayer insulating film is formed using a radiation-sensitive resin composition containing a Q polymer and an R sensitizer,

the Q polymer is a polymer containing a first structural unit having an acidic group, a second structural unit having an oxetanyl group or an oxetanyl group, and a third structural unit having a main chain structure different from that of the first structural unit and the second structural unit,

the first structural unit is a structural unit derived from at least one compound selected from the group consisting of (meth) acrylic acid and unsaturated carboxylic acid anhydride,

the second structural unit is a structural unit derived from at least one compound selected from the group consisting of glycidyl (meth) acrylate, 3, 4-epoxycyclohexylmethyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate glycidyl ether, and 3- (meth) acryloyloxymethyl-3-ethyloxetane.

2. The method for manufacturing a liquid crystal element according to claim 1, further comprising the steps of: by polymerizing the photopolymerizable monomer mixed in the liquid crystal layer, an alignment control layer for controlling the alignment of the liquid crystal is formed at the interface on each substrate side in the liquid crystal layer.

3. The method for manufacturing a liquid crystal element according to claim 1 or 2, wherein the liquid crystal aligning agent contains at least one of the A solvents and at least one of the B solvents.

4. The method for manufacturing a liquid crystal element according to claim 1 or 2, wherein the liquid crystal aligning agent contains a P polymer, and the P polymer is at least one selected from the group consisting of polyamic acid, polyamic acid ester, polyimide, and polyorganosiloxane.

5. The method for producing a liquid crystal element according to claim 1 or 2, wherein the liquid crystal aligning agent contains a p-polymer, the p-polymer being at least one selected from the group consisting of polyamic acid, polyamic acid ester, and polyimide,

the p-polymer has a partial structure derived from a tetracarboxylic acid derivative having at least one ring structure selected from the group consisting of a cyclobutane ring, a cyclopentane ring and a cyclohexane ring.

6. The method for manufacturing a liquid crystal element according to claim 1 or 2, wherein the liquid crystal aligning agent contains the following polymers: the polymer has at least one selected from the group consisting of a radical polymerizable group, a photoinitiator group, a radical polymerization inhibitor group, a nitrogen-containing heterocyclic ring, an amino group, and a protected amino group, wherein the imide ring of the polyimide is excluded from the nitrogen-containing heterocyclic ring.

7. The method for manufacturing a liquid crystal cell according to claim 1 or 2, wherein the liquid crystal aligning agent contains a polymer having a partial structure represented by the following formula (3):

*-L¹-R¹¹-R¹²-R¹³-R¹⁴···(3)

in the formula (3), L¹is-O-, -CO-, -COO-)¹、-OCO-*¹、-NR¹⁵-、-NR¹⁵-CO-*¹、-CO-NR¹⁵-*¹C1-C6 alkanediyl, -O-R¹⁶-*¹or-R¹⁶-O-*¹Wherein R is¹⁵Is a hydrogen atom or a C1-10 monovalent hydrocarbon group, R¹⁶An alkanediyl group having 1 to 3 carbon atoms; "*¹"represents and R¹¹A binding bond of (a); r¹¹And R¹³Each independently a single bond, phenylene or cycloalkylene,R¹²is a single bond, phenylene, cycloalkylene, -R¹⁷-B¹-*²or-B¹-R¹⁷-*²Wherein R is¹⁷Is phenylene or cycloalkylene, B¹is-COO-)³、-OCO-*³Or a C1-3 alkanediyl group; "*²"represents and R¹³Bond, "" of³"represents and R ¹⁷A binding bond of (a); r¹⁴A hydrogen atom, a fluorine atom, an alkyl group having 1 to 18 carbon atoms, a fluoroalkyl group having 1 to 18 carbon atoms, an alkoxy group having 1 to 18 carbon atoms, a fluoroalkoxy group having 1 to 18 carbon atoms, or a hydrocarbon group having 17 to 51 carbon atoms and having a steroid skeleton, and may have a radical polymerizable group or a photoinitiator group; wherein, in R¹⁴When R is a hydrogen atom, a fluorine atom or a group having 1 to 3 carbon atoms¹¹、R¹²And R¹³Not all are single bonds; "" indicates a bond.

8. The method for manufacturing a liquid crystal element according to claim 1 or 2, wherein a liquid crystal driving element and a color filter layer are formed over the substrate over which the interlayer insulating film is formed.

9. The method for manufacturing a liquid crystal element according to claim 1, wherein the Q polymer has at least one selected from the group consisting of a (meth) acryloyl group and a vinyl group.

10. The method for manufacturing a liquid crystal element according to claim 1, wherein the R sensitizer is at least one selected from the group consisting of a photo radical polymerization initiator, a photoacid generator, and a photobase generator.

11. The method for manufacturing a liquid crystal element according to claim 1, wherein the third structural unit is a structural unit derived from at least one compound selected from the group consisting of styrene, α -methylstyrene, 4-methylstyrene and 4-hydroxystyrene.